The effective delivery of hydrophobic therapeutic agents remains a challenging problem for the pharmaceutical industry. These challenges relate to the difficulty in formulating these therapeutic agents in vehicles for administration. Historically, hydrophobic therapeutic agents are administered in delivery vehicles that are less than advantageous with regard to delivery properties including therapeutic agent dose and bioavailability. Furthermore, serious side effects are occasionally observed associated with the vehicle itself.
The formulation of paclitaxel over the years is an example of the challenges associated with many hydrophobic therapeutic agents.
Paclitaxel is one of the most effective chemotherapeutic drugs and is used to treat mainly breast, lung and ovarian cancers. Taxol® is a paclitaxel formulation that utilizes a solvent, cremophor EL, to solubilize and deliver the essentially water-insoluble paclitaxel. Disadvantages and side effects of Taxol® are directly associated this solvent.
Paclitaxel has also been formulated as nanoparticles. Abraxane® is a nanoparticle paclitaxel formulation having improved paclitaxel solubility (0.35-0.7 μg/mL) compared to Taxol® and avoids the use of a harmful solvent. Abraxane® is a human serum albumin-coated paclitaxel nanoparticle. Cynviloq®, a polymeric micelle paclitaxel formulation that uses a biocompatible chemical polymer rather that a biological polymer to stabilize the nanoparticle, is a next-generation paclitaxel product.
Despite the advances in the development of alternative formulations that overcome the disadvantages associated with known hydrophobic therapeutic agent formulations, a need exists for new formulations of hydrophobic therapeutic agents having improved properties. The present invention seeks to fulfill these needs and provides further related advantages.